"In March we announced that CalDAV, an open standard for accessing calendar data across the web, would become a partner-only API because it appeared that almost all the API usage was driven by a few large developers. Since that announcement, we received many requests for access to CalDAV, giving us a better understanding of developers' use cases and causing us to revisit that decision. In response to those requests, we are keeping the CalDAV API public. And in the spirit of openness, today we're also making CardDAV - an open standard for accessing contact information across the web - available to everyone for the first time." Good move. Great for independent, small projects, specifically.